/// <summary>
/// Collects all alternative branches from this step.
/// If it returns only one transition is not an alternative branch but a normal transition.
/// </summary>
private static List <SfcTransition> CollectUpperAlternativeBranches(SfcStep source, int patchId, ProgrammableLogicController pu)
{
List <SfcTransition> transitions = new List <SfcTransition>();
List <int> collected = Collector.CollectHorizontal(patchId, pu.SfcProgramData, BranchType.Single, true);
foreach (int step in collected)
{
if (pu.SfcProgramData.SfcEntity.Lookup(step).ContainsTransition())
{
SfcTransition transition = CreateTransition(step, pu);
transition.DependingSteps.Add(source);
transitions.Add(transition);
}
else
{
int lowerStepId = step + 1;
PatchEntity lowerEntry = pu.SfcProgramData.SfcEntity.Lookup(lowerStepId);
if (lowerEntry != null && lowerEntry.SfcStepType == StepType.Pass)
{
transitions.AddRange(CollectUpperAlternativeBranches(source, lowerStepId, pu));
}
}
}
return(transitions);
}
/// <summary>
/// Creates a new SfcTransition with the given transitionPatchId
/// </summary>
private static SfcTransition CreateTransition(int transitionPatchId, ProgrammableLogicController pu)
{
string transitionText = pu.SfcProgramData.SfcEntity.Lookup(transitionPatchId).TransitionText;
BooleanExpression expression = TransitionMaster.InterpretTransitionText(transitionText, pu);
SfcTransition transition = new SfcTransition(expression, transitionPatchId);
return(transition);
}
/// <summary>
/// Assigns all destinations to this transition
/// </summary>
public static void AssignTransitionDestinations(SfcTransition transition, SfcProgramData data)
{
List <SfcStep> lowerTargets = CollectLowerSimultaneousBranches(transition.Id, data);
if (lowerTargets == null || lowerTargets.Count > 0)
{
transition.NextSteps = lowerTargets;
}
else
{
SfcStep alternativeStep = FindAlternativeMergeTarget(transition.Id, data);
List <SfcStep> alternativeList = new List <SfcStep>(1);
if (alternativeStep != null)
{
alternativeList.Add(alternativeStep);
}
transition.NextSteps = alternativeList;
}
}
/// <summary>
/// Collects all Simultaneous branches to merge from this step.
/// null if there is none.
/// </summary>
private static List <SfcTransition> CollectUpperSimultaneousMerge(int sourceId, ProgrammableLogicController pu)
{
List <int> collected = Collector.CollectHorizontal(sourceId, pu.SfcProgramData, BranchType.Double, true);
if (collected.Count <= 1)
{
PatchEntity currentPatch = pu.SfcProgramData.SfcEntity.Lookup(sourceId);
int lowerId = sourceId + 1;
PatchEntity lowerPatch = pu.SfcProgramData.SfcEntity.Lookup(lowerId);
if (!currentPatch.ContainsTransition() && lowerPatch != null && lowerPatch.SfcStepType == StepType.Pass)
{
return(CollectUpperSimultaneousMerge(lowerId, pu));
}
return(null);
}
PatchEntity transitionPatch = FindSimultaneousTransition(collected, pu.SfcProgramData);
List <SfcStep> connectedSteps = CollectConnectedSteps(collected, pu.SfcProgramData);
SfcTransition transition = CreateTransition(transitionPatch.Key, pu);
transition.DependingSteps = connectedSteps;
return(new List <SfcTransition> {
transition
});
}